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171.
细旦涤纶的氧等离子体改性清洁工艺研究   总被引:7,自引:0,他引:7  
采用氧低温等离子体技术对细旦涤纶进行改性以提高其染色上染率,并探讨了氧等离子体放电时间、放电气压和放电功率对细旦涤纶各项性能的影响规律。  相似文献   
172.
浅议橡胶废水处理技术   总被引:4,自引:0,他引:4  
唐勤 《云南环境科学》2003,22(Z1):137-138
论述了生物载体生化法处理橡胶废水的工艺技术.通过生产性试验和正在用该工艺运行的两家橡胶加工厂废水处理情况看,COD的去除率可达95%以上,出水水质稳定,可达标排放.运行成本为0.35元/m3,经济效益和环境效益都很显著.  相似文献   
173.
研究了染整废水中氧转移的速率,为工程设计、曝气机选择及动力效率测定,提供了科学理论依据。  相似文献   
174.
Duchenne and Becker muscular dystrophy (D/BMD) are usually problematical when trying to determine the carrier status of at-risk women, which usually has to be based on haplotype or dosage analysis on Southern blots. Using multiplex polymerase chain reaction (PCR) analysis, we have detected deletions in 20 out of 44 D/BMD families with living affected members (45·5 per cent), more often in sporadic cases of DMD (14/22 with detectable deletion) than in familial ones (4/15), the majority (15/20) occurring in the distal region of the D/BMD gene. Four highly informative short tandem repeat polymorphisms (STRPs), which lie within the distal deletion hot spot of the D/BMD gene, can show loss of heterozygosity in carrier females, providing direct evidence of their carrier status. These STRPs greatly improve informativity, with a combined heterozygosity of 100 per cent and with the majority of families informative for three of the four STRPs. In 14/15 (93 per cent) of the families with distal deletions, the STRPs provided direct information on carrier status, and in some cases, they provide valuable information on recombination breakpoints and non-paternity.  相似文献   
175.
We report the results of carrier and prenatal diagnosis for hypoxanthine guanine phosphoribosyltransferase (HPRT) deficiency, Lesch—Nyhan syndrome, by carrier testing of 83 women and prenatal analysis of 26 pregnancies. Our diagnostic methodologies include mutation detection and linkage analysis for probands and their families and biochemical measurement of HPRT enzyme activity for at-risk pregnancies. Identification of the mutation in the index case of each family permits precise carrier diagnosis using polymerase chain reaction (PCR) amplification of HPRT gene sequences and automated DNA sequencing. We demonstrate 100 per cent sensitivity for the detection of mutations in the HPRT gene of affected males and highly efficient carrier testing of at-risk females. Two other molecular methods proven to have high utility include PCR-based dosage analysis and linkage analysis by PCR amplification of a short tandem repeat (STR) in intron 3 of the HPRT gene. As a result, 45 at-risk women, 56 per cent of those tested, were identified not to be carriers of their family's HPRT gene mutation. Seven of these women were the mothers of affected males and prenatal testing for future pregnancies was recommended because of the possibility of gonadal mosaicism. Thirty-eight of these women were more distant relatives of affected males, thereby eliminating the need for future prenatal procedures. These studies illustrate the utility and precision of molecular methodologies for carrier and prenatal diagnosis of Lesch—Nyhan syndrome. These studies also illustrate that molecular diagnostic studies of affected males and carrier testing prior to pregnancy can clarify genetic risk predictions and eliminate unnecessary prenatal procedures.  相似文献   
176.
提出一种城市生活污水处理新工艺。以浮选 -浮动填料生化进行城市污水处理全流程 ,与国内外目前污水处理方法相比 ,其特点是 :占地少、投资省、抗冲击性强、适应范围大、处理负荷、容积负荷和污泥浓度大大提高 ,处理后水质高于二级城市污水处理厂出水水质 ,可以达到“国家城市回用水水质标准  相似文献   
177.
介绍了济南炼油厂污水处理场在减少外排剩余污泥方面的方法和遇到的问题,及对无剩余污泥生产的展望。  相似文献   
178.
好氧生物处理污染水体的供氧技术   总被引:2,自引:0,他引:2  
针对好氧生物处理污染水体需要充足的溶解氧,阐述了氧传递原理、传统供氧技术(机械供氧,鼓风供氧、氧载体供氧)和新型供氧技术(射流曝气供氧、膜供氧)。指出氧载体供氧和膜供氧技术具有广阔的应用前景。从材料,工艺及应用等方面详细介绍了膜供氧技术的研究进展,并对其发展前景进行了展望。  相似文献   
179.
生物接触氧化法处理有机废水的进展   总被引:13,自引:0,他引:13  
江萍  黎俊 《环境与开发》2000,15(4):6-7,28
本文综述了生物接触氧化法在固定化载体(填料),反应器及工艺等方面研究的新进展,重点介绍了极具推广价值的废水处理新工艺--曝气生物滤池及新型陶瓷粒状填料。  相似文献   
180.
The potential of fly ash to dechlorinate and destroy PCDD, PCDF and PCB was tested under oxygen deficient conditions in the laboratory. Specifically, two types of fly ash were compared, originating either from a fluidized bed incinerator using Ca(OH)2 spray (FA1), or a stoker incinerator without Ca(OH)2 impact (FA2).

Results from the present study indicate that on FA2 type fly ash, the degradation processes of OCDD, OCDF and D10CB occurred primarily via dechlorination/hydrogenation up to temperature settings of 340 °C. In contrast, FA1 type fly ash was found to effect both dechlorination and destruction of these compounds already at temperature settings of 260 °C.

The dechlorination velocity of PCDD and PCDF did not differ significantly. However, the first dechlorination step of OCDF in the 1,9-position occurred faster compared to the first dechlorination step of OCDD.

The isomer pattern resulting from the dechlorination processes was quite similar on both FA1 and FA2, indicating that differences in alkalinity or elemental composition of the two types of fly ashes do not have a significant influence on the position of dechlorination. PCDD and PCDF dechlorination of the 2,3,7,8-positions was not favoured over dechlorination of the 1,4,6,9-positions on either type of fly ash. In contrast, dechlorination of PCB occurred predominantly on the toxicological relevant 3- and 4-positions.

The dechlorination/destruction processes were completed on both types of fly ash at 380 °C within one hour, which correlates well with results obtained from actual plant operation practices.  相似文献   

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